Self-propelling apparatus for a vacuum cleaner

ABSTRACT

A self-propelling apparatus for a vacuum cleaner in which a cleaner body is pivotably mounted to a brush assembly is provided. The self-propelling apparatus includes a sensor unit having a wheel part that pivots in the opposite direction to a moving direction of the vacuum cleaner, a connection part connected with the wheel part and fixed to the brush assembly by one end thereof and a switch part turned on and off according to the connection part, and generating progression and retrogression signals according to pivoting motion of the wheel part, and an interception unit generating an interception signal when the cleaner body is in an upright posture, and a driving unit moving the vacuum cleaner in accordance with the progression and retrogression signals.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims benefit under 35 U.S.C. § 119(a) of KoreanPatent Application No. 2005-35382, filed Apr. 28, 2005, the entirecontents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a self-propelling apparatus for avacuum cleaner, capable of automatically driving the vacuum cleanerforward and backward.

2. Description of the Related Art

An example of a vacuum cleaner is disclosed in U.S. Pat. No. 6,282,747,the vacuum cleaner in which, when an operator grips a handle and moves acleaner body forward or backward, such an action of the operator istransmitted to a driving module through a linkage mechanism connected tothe handle so that the vacuum cleaner is automatically driven forwardand backward. U.S. Pat. No. 6,158,084 discloses another vacuum cleanercapable of automatically moving forward and backward as the operator'saction is transmitted to a transmission through a cable connected to thehandle. Yet another vacuum cleaner is disclosed in Japanese PatentPublication No. H5-68656, the vacuum cleaner automatically movingforward and backward by detecting torque applied to a driving wheel androtating a running motor forward and backward. Using the self-propellingapparatus as described in the above examples, once driven forward orbackward, the vacuum cleaner automatically keeps the forward or backwardmotion without further application of a force. Therefore, the cleaningwork becomes convenient, especially, even on an uneven surface, such ascarpet, hindering smooth travel of the vacuum cleaner due to highresistance.

However, in such vacuum cleaners disclosed in the U.S. Pat. No.6,282,747 and U.S. Pat. No. 6,158,084, while being transmitted through aconnection means such as the linkage mechanism or the cable, theoperator's intention for driving vacuum cleaner forward and backward maybe misunderstood or failed. This may cause malfunction of theself-propelling apparatus, thereby deteriorating reliability of theapparatus. Also, the connection means such as the linkage mechanism orthe cable complicates the structure and increases the manufacturing costof the apparatus.

Furthermore, a torque detector as employed in Japanese PatentPublication No. H5-68656 induces problems of the complex structure andthe high manufacturing cost. In addition, repetitive use of the electrictorque detector may deteriorate reliability and durability of theapparatus.

SUMMARY OF THE INVENTION

An aspect of the present invention is to solve at least the aboveproblems and/or disadvantages and to provide at least the advantagesdescribed below. Accordingly, an aspect of the present invention is toprovide a self-propelling apparatus for a vacuum cleaner capable ofcorrectly transmitting an operator's intention of moving the vacuumcleaner forward and backward.

A second aspect of the present invention is to provide a vacuum cleanerfor a vacuum cleaner, improved in reliability and durability.

A third aspect of the present invention is to provide a simplystructured vacuum cleaner.

In order to achieve the above-described aspects of the presentinvention, there is provided a self-propelling apparatus for a vacuumcleaner in which a cleaner body is pivotably mounted to a brushassembly, comprising a sensor unit mounted to the brush assembly andhaving a wheel part which pivots in the opposite direction to a movingdirection of the vacuum cleaner to generate progression andretrogression signals according to pivoting motion of the wheel part;and a driving unit moving the vacuum cleaner in accordance with theprogression and retrogression signals.

The sensor unit comprises a connection part connected with the wheelpart and fixed to the brush assembly by one end thereof; and a switchpart turned on and off according to the connection part. The wheel partcomprises a wheel contacted with a surface being cleaned; a housingsupporting the wheel; and a housing shaft disposed on an upper portionof the housing, and pivots in contact with the surface being cleaned byinertia and friction with the surface being cleaned.

The connection part comprises a link member including a first via-holefor insertion of the housing shaft and a second via-hole for pivotablemounting to the brush assembly; a resilient member disposed between thelink member and the housing and fit around the housing shaft; a firstconnection member fit with the housing shaft through the first via-holeso as to restrain escape of the link member from the housing shaft; anda second connection member fit with the brush assembly through thesecond via-hole so that the link member can pivot on the brush assembly.

The switch part comprises a first switch disposed on the right of thelink member and pressed by a right side of the link member to therebygenerate a progression signal; and a second switch disposed on the leftof the link member and pressed by a left side of the link member tothereby generate a retrogression signal. The switch part furthercomprises a switch cover for shielding and fixing the first and thesecond switches to the brush assembly.

The driving unit comprises a power part mounted to the brush assembly;and a circuit part processing the progression and retrogression signalsand an interception signal so as to operate and stop the power part.

The self-propelling apparatus may further comprise an interception unitwhich generates the interception signal when the cleaner body is in anupright posture, and wherein the interception unit comprises a levermounted to the cleaner body; and a third switch mounted to the brushassembly and pressed by the lever when the cleaner body is in theupright posture.

Another aspect of the present invention is achieved by providing aself-propelling apparatus for a vacuum cleaner in which a cleaner bodyis pivotably mounted to a brush assembly, comprising a sensor unitincluding a wheel part which pivots in the opposite direction to amoving direction of the vacuum cleaner, a connection part connected withthe wheel part and fixed to the brush assembly by one end thereof and aswitch part turned on and off according to the connection part, andgenerating progression and retrogression signals according to pivotingmotion of the wheel part, and an interception unit generating aninterception signal when the cleaner body is in an upright posture, anda driving unit moving the vacuum cleaner in accordance with theprogression and retrogression signals.

BRIEF DESCRIPTION OF THE DRAWING FIGURES

The above aspect and other features of the present invention will becomemore apparent by describing in detail exemplary embodiments thereof withreference to the attached drawing figures, wherein;

FIG. 1 is a perspective view of a self-propelling apparatus according toan embodiment of the present invention;

FIG. 2 shows a brush assembly, without an upper cover, and a main bodyslantingly connected to the brush assembly;

FIG. 3 is an exploded, perspective view of a sensor unit of FIG. 2;

FIG. 4 shows a link member disposed in a neutral position between afirst switch and a second switch;

FIG. 5 shows the link member as rotated and pressing the first switch;

FIG. 6 shows the link member as rotated and pressing the second switch;and

FIG. 7 shows a main body in an upright posture so that a lever presses athird switch.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

Hereinafter, an embodiment of the present invention will be described indetail with reference to the accompanying drawing figures.

In the following description, same drawing reference numerals are usedfor the same elements even in different drawings. The matters defined inthe description such as a detailed construction and elements are nothingbut the ones provided to assist in a comprehensive understanding of theinvention. Thus, it is apparent that the present invention can becarried out without those defined matters. Also, well-known functions orconstructions are not described in detail since they would obscure theinvention in unnecessary detail.

Referring to FIG. 1, a vacuum cleaner 100 comprising a cleaner body 110,a brush assembly 120, and a self-propelling apparatus 130 is shown.

The cleaner body 110 is mounted to the brush assembly 120 to pivot indirections A and B illustrated as arrows. The cleaner body 110 has, atan upper portion thereof, a handle 111 having an on/off switch 111 a.Additionally, the cleaner body 110 comprises therein a dust separator112 and a dust receptacle 113.

The brush assembly 120 is disposed at a lower portion of the cleanerbody 110 to draw in dust from a surface being cleaned. For this, thebrush assembly 120 comprises a lower frame 121 having a suction port 121a (FIG. 2), an upper cover 122 for shielding the lower frame 121, and amain wheel 123 rotatably mounted on each side of the brush assembly 120.

As an operator drives the vacuum cleaner 100 on the surface beingcleaned forward and backward as shown by arrows C and D, the dust on thesurface being cleaned is drawn into the dust separator 112 through thesuction port 121 a (FIG. 2) separated in the dust separator 112, andcollected in the dust receptacle 113.

With reference to FIG. 2, once applied with a force forward or backwardby the operator, the vacuum cleaner 100 is continuously propelledforward or backward without further application of the force. To thisend, the self-propelling apparatus 130 comprises a driving unit 200, asensor unit 300, and an interception unit 400.

The driving unit 200 includes a power part 210 and a circuit part 220.

The power part 210 comprises a propelling motor 211, a gearbox 212, andleft and right auxiliary wheels 213 a and 213 b. The propelling motor211 rotates the left and right auxiliary wheels 213 a and 213 b forwardand backward. The gearbox 212 decelerates the propelling motor 211 at anappropriate ratio and transmits the decelerated speed of the propellingmotor 211 to the left and right auxiliary wheels 213 a and 213 b.

The circuit part 220 processes signals generated in first and secondswitches 331 and 332 (FIG. 3), which are implemented by a micro switch,and a third switch 420 to thereby operate or stop the power part 210.More specifically, the circuit part 220 rotates the propelling motor 211forward upon transmission of a progression signal generated in the firstswitch 331 (FIG. 3) thereto. As a retrogression signal generated in thesecond switch 332 (FIG. 3) is transmitted to the circuit part 220, thepropelling motor 211 is rotated backward. As an interception signalgenerated in the third switch 420 is transmitted to the circuit part220, the circuit part 220 stops the propelling motor 211 regardless ofgeneration of the progression and the retrogression signals of the firstand the second switches 331 and 332 (FIG. 3).

Referring to FIG. 3, the sensor unit 300 comprises a wheel part 310, aconnection part 320, and a switch part 330.

The wheel part 310 operates in contact with the surface being cleaned.The wheel part pivots in response to movement of the vacuum cleaner 100due to inertia and friction. As shown in FIGS. 1 and 3, for example,when the vacuum cleaner 100 moves in an arrowed direction C, the wheelpart 310 pivots in an arrowed direction E, which is substantiallyopposite to direction to the arrowed direction C. When the vacuumcleaner 100 moves in an arrowed direction D, the wheel part 310 pivotsin an arrowed direction F, that is, substantially opposite to thearrowed direction D. For this, the wheel part 310 comprises a wheel 311,a housing 312, a housing shaft 313, and a wheel shaft 314.

The wheel 311 directly contacts with the surface being cleaned. Thehousing 312 is formed as a frame of a flattened-U shape for enclosingand supporting the wheel 311 on the wheel shaft 314 so that the wheel311 can rotate about the wheel shaft 314. The housing shaft 313 isdisposed on an upper portion of the housing 312 and has a connectionrecess 313 a for coupling with a first connection member 323 in thecenter thereof.

The connection part 320 comprises a link member 321, a resilient member322, the first connection member 323, and a second connection member324. The link member 321 is comprised of a bent section whereon a firstvia-hole 321 a is formed and a straight section whereon a secondvia-hole 321 b is formed. The link member 321 can be connected with thewheel part 310 through inserting the housing shaft 313 into the firstvia-hole 321 a. As the second connection member 324 is inserted into thesecond via-hole 321 b, the link member 321 is connected with the brushassembly 120 (FIG. 2) for pivotal movement of the link member 321 aboutthe second connection member 324.

The resilient member 322 may be implemented by a coil spring disposedbetween the link member 321 and the housing 312 and fit around thehousing shaft 313. By the resilient member 322, the housing shaft 313being passed through the first via-hole 321 a of the link member 321 isable to elastically ascend and descend according to a height of thesurface being cleaned in arrowed directions G and H.

The first connection member 323 is inserted in the connection recess 313a of the housing shaft 313 through the first via-hole 321 a so that thelink member 321 is not released from the housing shaft 313 in thearrowed direction G The second connection member 324 is connected to thebrush assembly 120, passing through the second via-hole 321 b. A screwor a rivet may be used for the first and the second connection members323 and 324.

FIGS. 4 through 6 are views for explaining the pivoting operation of thelink member 321, wherein illustration of a switch cover 333 is omitted.Referring to FIGS. 3 and 4, the switch part 330 is turned on and off bythe connection part 320 and thereby generates the progression signal andthe retrogression signal. To this end, the switch part 330 includes thefirst switch 331, the second switch 332, and the switch cover 333.

The first switch 331 is disposed on the right of the link member 321 andhas a first switch projection 331 a, which is normally biased to anextended position. As the wheel 311 is pivoted in the arrowed directionE about the second connection member 324, the first switch projection331 a is pressed by a right side S1 of the link member 321. When thefirst switch projection 331 a is thus pressed as shown in FIG. 5, thefirst switch 331 is turned on to generate the progression signal and theprogression signal is transmitted to the circuit part 220.

The second switch 332 is disposed on the left of the link member 321 andhas a second switch projection 332 a, which is normally biased to anextended position. As the wheel 311 is pivoted in the arrowed directionF about the second connection member 324, the second switch projection332 a is pressed by a left side S2 of the link member 321. When thesecond switch projection 332 a is thus pressed as shown in FIG. 6, thesecond switch 332 is turned on to generate the retrogression signal andthe retrogression signal is transmitted to the circuit part 220.

The switch cover 333 shields above the first and the second switches 331and 332 and fixes the switches 331 and 332 to the brush assembly 120(FIG. 2). However, the first and the second switches 331 and 332 may bedirectly fixed to the brush assembly 120 (FIG. 2) without the switchcover 333. The switch cover 333 includes a second connection memberinsertion hole 333 a for penetration of the second connection member324. After inserting the second connection member 324 into the secondconnection member insertion hole 333 a, the second connection member 324pivotably mounts the link member 321 to the brush assembly 120 (FIG. 2).

The interception unit 400 comprises a lever 410 and the third switch 420in order to generate the interception signal, as shown in FIG. 2.

Referring to FIG. 7, the lever 410 is mounted to the cleaner body 110.The lever 410 presses the third switch 420 only when the cleaner body110 is erected (FIG. 1). However, the lever 410 does not press the thirdswitch 420 when the cleaner body 110 is pivoted with respect to thebrush assembly 120 in the arrowed direction B as shown in FIG. 2.

The third switch 420 is mounted to the brush assembly 120 and is pressedby the lever 410 when the cleaner body 110 is erected (FIG. 1).Therefore, as shown in FIG. 7, the third switch 420 has a third switchprojection 420 a which is pressed by the lever 410 when the cleaner body110 is erected. As the third switch projection 420 a is pressed by thelever 410, the third switch is turned on and thereby generates theinterception signal. Upon transmission of the interception signal to thecircuit part 220, the circuit part 220 stops the propelling motor 211regardless of generation of the progression and the retrogressionsignals.

The interception unit 400 is dispensable in the self-propellingapparatus 130. However, since the cleaner body 110 is usually inclinedby the operator during the cleaning work, it is preferable to equip theinterception unit 400 capable of detecting the inclination of thecleaner body 110 so that the self-propelling apparatus 130 is operatedonly upon detection of the inclination of the cleaner body 110.

Hereinbelow, the operation of the self-propelling apparatus 130 will bedescribed.

Referring to FIG. 1, when the operator moves forward the vacuum cleaner100 in the arrowed direction C, the wheel part 310 is rotated about thewheel shaft 314 and is pivoted about the second connection member 324 inthe direction E, that is, opposite to the moving direction of the vacuumcleaner 100 by inertia and friction of the wheel part 310 with thesurface being cleaned. With reference to FIG. 4, the link member 321connected with the wheel part 310 is also pivoted in the arroweddirection E, thereby being moved to a position shown in FIG. 5 from aposition shown in FIG. 4. Accordingly, the right side S1 of the linkmember 321 presses the first switch projection 331 a of the first switch331. The first switch 331 generates the progression signal and as shownin FIG. 2, the progression signal is transmitted to the circuit part220. The circuit part 220 rotates forward the propelling motor 211.Forward rotation oft he propelling motor 211 is transmitted to the leftand the right auxiliary wheels 213 a and 213 b, thereby propelling thevacuum cleaner 100 forward in the arrowed direction C. Thus, oncemovement in the arrowed direction C is initiated by the operator, thevacuum cleaner 100 can be kept moving in the arrowed direction C by theself-propelling apparatus 130 without the operator having to keeppropelling the vacuum cleaner 100 forward. If the operator forciblyseizes or stops the vacuum cleaner 100 from moving forward in thearrowed direction C, the link member 321 is pivoted in the arroweddirection F from the position shown in FIG. 5 to the position shown inFIG. 4 so that the first switch projection 331 a is no longer pressed.Accordingly, the first switch 331 quits generating and transmitting theprogression signal to the circuit part 220 so that the circuit part 220stops rotation of the propelling motor 211, and the forward running ofthe vacuum cleaner 100 in the arrowed direction C by the self-propellingapparatus 130 is stopped.

With reference to FIG. 1, when the operator moves backwards the vacuumcleaner 100 in the arrowed direction D, the wheel part 310 is rotatedabout the wheel shaft 314 and is pivoted about the second connectionmember 324 in the arrowed direction F, that is, opposite to the movingdirection of the vacuum cleaner 100 by inertia and friction with thesurface being cleaned. With reference to FIG. 4, the link member 321connected with the wheel part 310 is also pivoted in the arroweddirection F, thereby being moved to a position shown in FIG. 6 from aposition shown in FIG. 4. Accordingly, the left side S2 of the linkmember 321 presses the second switch projection 332 a of the secondswitch 332. The second switch 332 generates the retrogression signal andas shown in FIG. 2, the retrogression signal is transmitted to thecircuit pat 220. The circuit part 220 rotates backward the propellingmotor 211. Backward rotation of the propelling motor 211 is transmittedto the left and the right auxiliary wheels 213 a and 213 b, therebypropelling the vacuum cleaner 100 backward in the arrowed direction D.Thus, once movement in the arrowed direction D is initiated by theoperator, the vacuum cleaner 100 can be kept moving in the arroweddirection D by the self-propelling apparatus 130 without the operatorhaving to keep propelling the vacuum cleaner 100 backward. If theoperator forcibly seizes or stops the vacuum cleaner 100 from movingbackward in the arrowed direction D, the link member 321 is pivoted inthe arrowed direction E from the position shown in FIG. 4 to theposition shown in FIG. 6 so that the second switch projection 332 a isno longer pressed. Accordingly, the second switch 332 quits generatingand transmitting the retrogression signal to the circuit part 220 sothat the circuit part 220 stops rotation of the propelling motor 211,and the backward running of the vacuum cleaner 100 in the arroweddirection D by the self-propelling apparatus 130 is stopped.

When the cleaner body 110 is in the upright posture as shown in FIG. 7,the lever 410 presses the third switch projection 420 a. The thirdswitch 420 generates the interception signal. As the interception signalis transmitted to the circuit part 220, the circuit part 220 stops thepropelling motor 211 regardless of generation of the progression and theretrogression signals of the first and the second switches 331 and 332.Therefore, the vacuum cleaner 100 is not automatically moved forward andbackward only upon initial application of the force of moving the vacuumcleaner 100 forward and backward.

Above all, according to an embodiment of the present invention, theoperator's action for moving the vacuum cleaner 100 forward or backwardis transmitted through the wheel part 310 which is in direct contactwith the surface being cleaned. Accordingly, the operator's intentioncan be correctly delivered, thereby improving reliability.

Second, since the sensor unit 300 is mechanically structured,reliability and durability thereof can be enhanced in spite of repeateduse.

Third, since the structure does not demand a dedicated connectionmember, such as a linkage mechanism and cable, and a torque detector,simplified structure and low manufacturing cost can be implemented.

While the invention has been shown and described with reference tocertain embodiments thereof, it will be understood by those skilled inthe art that various changes in form and details may be made thereinwithout departing from the spirit and scope of the invention as definedby the appended claims.

1. A self-propelling apparatus for a vacuum cleaner in which a cleanerbody is pivotably mounted to a brush assembly, comprising: a sensor unitmounted to the brush assembly and having a wheel part which pivots inthe opposite direction to a moving direction of the vacuum cleaner togenerate progression and retrogression signals according to pivotingmotion of the wheel part; and a driving unit moving the vacuum cleanerin accordance with the progression and retrogression signals.
 2. Theself-propelling apparatus of claim 1, wherein the sensor unit comprises:a connection part connected with the wheel part and fixed to the brushassembly by one end thereof; and a switch part turned on and offaccording to the connection part.
 3. The self-propelling apparatus ofclaim 2, wherein the wheel part comprises: a wheel contacted with asurface being cleaned; a housing supporting the wheel; and a housingshaft disposed on an upper portion of the housing, and wherein the wheelpart pivots by inertia and friction due to contact of the wheel partwith the surface being cleaned.
 4. The self-propelling apparatus ofclaim 3, wherein the connection part comprises: a link member includinga first via-hole for insertion of the housing shaft and a secondvia-hole for pivotable mounting to the brush assembly; a resilientmember disposed between the link member and the housing and fit aroundthe housing shaft; a first connection member fit with the housing shaftthrough the first via-hole so as to restrain escape of the link memberfrom the housing shaft; and a second connection member fit with thebrush assembly through the second via-hole so that the link member canpivot on the brush assembly.
 5. The self-propelling apparatus of claim4, wherein the switch part comprises: a first switch disposed on theright of the link member and pressed by a right side of the link memberto thereby generate a progression signal; and a second switch disposedon the left of the link member and pressed by a left side of the linkmember to thereby generate a retrogression signal.
 6. Theself-propelling apparatus of claim 5, wherein the switch part furthercomprises a switch cover for shielding and fixing the first and thesecond switches to the brush assembly.
 7. The self-propelling apparatusof claim 1, wherein the driving unit comprises: a power part mounted tothe brush assembly; and a circuit part processing the progression andretrogression signals and an interception signal so as to operate andstop the power part.
 8. The self-propelling apparatus of claim 1,further comprising an interception unit which generates the interceptionsignal when the cleaner body is in an upright posture, and wherein theinterception unit comprises: a lever mounted to the cleaner body; and athird switch mounted to the brush assembly and pressed by the lever whenthe cleaner body is in the upright posture.
 9. A self-propellingapparatus for a vacuum cleaner in which a cleaner body is pivotablymounted to a brush assembly, comprising: a sensor unit including a wheelpart which pivots in the opposite direction to a moving direction of thevacuum cleaner, a connection part connected with the wheel part andfixed to the brush assembly by one end thereof and a switch part turnedon and off according to the connection part, and generating progressionand retrogression signals according to pivoting motion of the wheelpart; an interception unit generating an interception signal when thecleaner body is in an upright posture; and a driving unit moving thevacuum cleaner in accordance with the progression and retrogressionsignals.
 10. A self-propelling apparatus for a vacuum cleaner,comprising: a wheel part that pivots in a first direction in response toforward movement of the vacuum cleaner and a second direction inresponse to backward movement of the vacuum cleaner; a first switch on afirst side of said wheel part, said first switch being activated by saidwheel part when pivoted in said first direction so that said firstswitch generates a progression signal; a second switch on a second sideof said wheel part, said second switch being activated by said wheelpart when pivoted in said second direction so that said second switchgenerates a retrogression signal; and a propelling motor for moving thevacuum cleaner forward in response to said progression signal andbackward in response to said retrogression signal.
 11. Theself-propelling apparatus of claim 10, further comprising a circuit partprocessing said progression and retrogression signals and transmittingsaid progression and retrogression signals to said propelling motor. 12.The self-propelling apparatus of claim 10, further comprising a thirdswitch for generating an interception signal when the vacuum cleaner isin an upright posture.
 13. The self-propelling apparatus of claim 12,wherein said propelling motor stops moving the vacuum cleaner inresponse to said interception signal regardless of generation of saidprogression and retrogression signals.